Mechanical devices with flush or protruding shafts frequently use an annular fluid seal surrounding an end of the shaft. A portion of the seal is seated snugly within a recess in a bearing surrounding and supporting the shaft. At the end of many shafts is a threaded cavity for a bolt used to hold an implement to this end, For example, the implement may be a sprocket, pulley, shaft coupling, shaft balancer, or other component of the mechanical device.
The seal prevents leaking of internal fluids to the exterior of the mechanical device, and such a seal needs to be periodically removed and replaced, as it hardens and breakdowns over time, ceasing to function properly, so fluid leakage occurs. These shaft fluid seals are made of a supple material, but may include a steel reinforcing ring. The internal diameter of the seal is such so that the inner annular edge of the seal presses tightly against and around the shaft forming a barrier. Nevertheless, the seal is seated and mounted in a manner that enables the shaft to move, either to rotate or reciprocate, or both.
The seal barrier prevents fluids from flowing to the exterior of the mechanical device through the interface between the shaft sidewall and the edge of the seal abutting this sidewall. Conventional removal of seals is accomplished using a metal or plastic pick. The pick is manually slid in one direction along the shaft and under the inner seal edge, catching the edge, and then pulling on the seal in the opposite direction to deform and remove the seal. Using a pick accelerates shaft wear and sometimes causes damage to the shaft, resulting in loss of sealing properties if the shaft is worn or damaged by gouging or scratching.